With the development of mobile communication techniques, base station architectures evolve from a first generation, a second generation to a new form of base station architecture represented currently by an active antenna. In the first generation base station architecture, a Base Transceiver Station (BTS) integrates a base band and an RF transceiver unit, and transmits an RF signal to an antenna through an RF cable, and in this architecture the transmission insertion loss in the RF cable is great and thus the transmission power loss is great. The second generation base station architecture is namely the currently mainstream architecture of Building Base band Unit (BBU) and Remote Radio Unit (RRU), wherein in the downlink direction the BBU transmits a base band signal to the RRU through an optical fiber, after completing a digital IF processing, the RRU converts the base band signal to an RF signal and transmits it to an antenna via an RF jumper; while in the uplink direction, the antenna transmits an RF signal to the RRU through the RF jumper, after processed by the RRU, the RF signal becomes a base band signal and then it is transmitted to the BBU via the optical fiber. For this architecture, the RF transceiver unit is very close to the antenna, thus reducing the insertion loss caused by the RF jumper from the RRU to the antenna and improving the efficiency.
In a mobile communication system, in order to reduce as far as possible the feed line loss caused by overlong cable from a base station under a tower and an antenna on the tower, there is a trend of moving the base station to the tower, thus corresponding product modalities gradually appear. In a new modality with an active antenna as the base station architecture, a BBU also transmits a base band signal to an active antenna unit, differences compared to the architecture of BBU and RRU lie in that the active antenna divides transmission/reception channels into the scale of antenna elements, thus leading to a finer graininess. By different configurations of the active antenna elements, functions of flexible beam control and Multiple Input Multiple Output (MIMO) in practical communication networking can be achieved, thus implementing more flexible resource dynamic configuration and sharing, so as to achieve the objectives of a lower networking cost for a whole network and optimal whole-network performance.
An active antenna system is a multiple transmission/reception channel system. In an active antenna product, a plurality of transmission/reception channels are correspondingly configured with a plurality of antenna arrays, respective antenna array operates in a parallel operation state, and each path of antenna array corresponds to transmission/reception channel and a corresponding digital base band processing portion. The transmission/reception channel includes many analog circuits, which consist of a large number of IF/RF components with high voltage, high power and high current. Operation temperatures of these components are very high, thus a long time of operation readily causes aging, thereby resulting in failure of some components and thus affecting reliability of the system. Therefore, the state of the transmission/reception channel needs to be detected in real time so that the system can operate normally.
At present, a dedicated calibration channel can be used to detect in real time the state of a transmission/reception channel, and the implementation flow may include: detecting in real time respective beam forming coefficients of the plurality of transmission/reception channels to detect whether a failure occurs in respective paths of transmission/reception channels; when it is detected that a failure occurs in any one of the plurality of transmission/reception channels, acquiring a current set of beam forming coefficients corresponding to all transmission/reception channels and failure mode information corresponding to a current failed transmission/reception channel; performing optimizing processing on the current set of beam forming coefficients using a preset optimization algorithm, so as to calculate and obtain a set of beam forming coefficients with respect to the current set, i.e., a first set of beam forming coefficients more adapted to the failure mode information; and updating correspondingly beam forming coefficients of respective transmission/reception channels according to the first set of beam forming coefficients.
FIG. 1 is a structural diagram of a device corresponding to the existing method for detecting a state of a transmission/reception channel. As shown in FIG. 1, a dedicated calibration channel needs to be arranged to perform date acquisition, that is to say, extra analog and digital circuits are required to be arranged to perform data acquisition, thus leading to extra cost and power loss. During implementation of the existing detection method, digital signals of the calibration channel need to be acquired and calculated in real time, thus the complexity of design of switch control arrays is increased, thereby causing some pressure to the selection of base band digital devices and increasing cost of digital devices.